Loan amortization schedule API, pay-per-request via x402 on Base (USDC).
What it does
This endpoint at lowpaymentfee.com returns a loan amortization schedule for a specific loan (loan ID 58 in the URL path). It is part of a broader platform offering various pay-per-call APIs spanning data analytics, AI/ML inference, finance, crypto, and utility services — all gated behind the x402 payment protocol on the Base network using USDC.
The specific endpoint `/api/v1/loans/58/schedule` accepts POST requests and returns JSON. The x402 challenge advertises a maximum cost of 20,000 base units of USDC (0x8335… on Base), which equals $0.02 per request (USDC uses 6 decimals). This aligns with the site's stated flat pricing of $0.02 per request across all endpoints. Payment is settled on-chain to the provider's wallet, with no API keys, rate limits, or subscriptions required.
Documentation is extremely sparse — the docs, pricing, API, and README pages all render only a "Connect wallet" prompt with no substantive content. There is no OpenAPI schema, no request/response examples, and no description of what fields the loan schedule returns or what input parameters the POST body expects. The endpoint path suggests it is tied to a fixed loan ID (58), which raises questions about whether other loan IDs are available or how a caller would discover them. The platform appears to be a demonstration or early-stage deployment of x402-gated APIs.
Capabilities
Use cases
- —Retrieve a loan amortization schedule showing payment breakdowns over time
- —Integrate loan schedule data into financial planning tools
- —Automate loan analysis workflows with per-call payment
Fit
Best for
- —Agents needing on-demand loan schedule data without API key registration
- —Developers experimenting with x402 pay-per-call finance APIs
- —Prototyping financial applications with instant crypto-settled access
Not for
- —Production loan origination systems requiring configurable loan parameters (no docs on input schema)
- —Users needing bulk or high-volume loan calculations at lower per-call cost
- —Anyone requiring detailed API documentation or SLA guarantees
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/loans/58/schedule \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing ($0.02 USDC on Base). However, there is no documentation, no OpenAPI schema, no request/response examples, and the endpoint path is hardcoded to a single loan ID with no explanation of parameters or output format. Effectively a stub listing.
Warnings
- —No API documentation available — docs, pricing, and README pages all render only a wallet-connect prompt
- —No OpenAPI or request/response schema provided; input parameters for the POST body are unknown
- —Endpoint path is hardcoded to loan ID 58; unclear if other loan IDs exist or how to discover them
- —Platform appears to be early-stage or a demonstration deployment
Citations
- —The x402 challenge advertises maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/loans/58/schedule
- —The site states flat pricing of $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/loans/58/schedule